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Full text of "Hydro-electric power station design"

ARMOTTR 

INSTITUTE OF TECHNOLOGY 

UBRAH.Y 



ARMOUR 

INSTITUTE OF TECHNOLOGY 

LIBRARY 



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HYDROELECTRIC 

POWER STATION 

DESIGN 

A THESIS 

PRESENTED BY 

H. RALPH BADGER 

ROY G. GRANT 

HAROLD W. NICHOLS 

TO THE 

PRESIDENT AND FACULTY 

OF 

ARMOUR INSTITUTE OF TECHNOLOGY 

FOR THE DEGREE OF 

BACHELOR OF SCIENCE IN ELECTRICAL ENGINEERING 

HAVING COMPLETED THE PRESCRIBED COURSE OF STUDY IN 

ELECTRICAL ENGINEERING 

'LU..«.ouoi ii uit OF TECHNOLOGY / / 

PAUL V. GALVIN LIBRARY ■ -f J^> 

35 WEST 33RD STREET ^^E^^T^^/ L«_~^ ^^^-^JL 

CHICAGO, IL 60616 ~ 

^J 9 C^Ly .<4£^ul\ 



PREFACE. 

The subject of "Jfy-dro-Electric Power Station 
Design" has herein "been presented in two parts :- 

the first - a brief treatise on the general princi- 
ples and important factors, and the second - an 
application of these to a particular case. 

In Part I. is given a general statement and 
analysis of the important factors entering into 
the design of such power generating stations. 

In Part II. the actual design of a station 
for a particular location is undertaken. This pro- 
posed station to be located on the Snake River in 
the south-central part of the state of Idaho, and 
to receive its water supply from the Malad - a tri- 
butary of the Snake River. 

H. H.B. 
R.G.G. 



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TABLE OF CONTENTS 





Page. 


Preface 


2 


Table of Contents 


3 


List of Illustrations 


4 


Part I. 




Introduction 


6 


The General Problem 


6 


"Water supply 


9 


Exact Location of the Plant 


18 


Parts of the Project 


20 


Power House Equipment 


27 


Part II. 




Introduction 


47 


The General Problem 


47 


The water Supply 


48 


General Lay-out of Project 


62 


Power station Building and Equipment 


52 


Transmission of Porer 


61 


Appendix. 




Bibliography 


64 


Prices and Cost Items 


65 




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LIST OF ILLUSTRATIONS. 

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61 
after 60 



I. 


Map of Idaho 


II. 


Map of Project 




Drawings of station. 


III. 


Main Floor Plan 


IV. 


Second Floor Plan 


V. 


Transverse Section 


VI. 


Gross Section 


VII. 


TTiring Diagram 


VIII. 


Switchboard 



IX. Hydraulic Turbine 



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Part l« 

A Brief Treatise on the General 
Principles and Important Factors Enter- 
ins Into the Design of Hydro-Electric 
PoT?er Generating stations. 



Hydro-Electric Power station Design 

Introduction. 
A consideration of the subject of "Hydro-Elec- 
tric Power station Design" entails a discussion of 
the location of the market for sale of power, nat- 
ure and extent of the water supply of the source 
of power, auxiliary construction for water handling, 
location, construction and equipment of generating 
station* transmission and distribution of energy. 

The General Problem. 
Electrical energy is now in nearly universal 
demand. The amount of this commodity that is made 
use of in any section of country varies within 
wide limits. For its common usages - in power and 
lighting - this variation is nearly directly with 
the population, though there is a constantly incre- 
asing demand for it in railway work - outside of 
centers of population, with the increased price 
of coal, as well as for other disadvantages inhe- 
rent in steam production,- other means than indi- 
rectly from coal, of generating electric current, 



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Itydro-Electric Power Station Design 

are "being rapidly sought and utilized. Chief among 
these t in present importance, is the water power of 
natural sources. 

As these cannot he located where wanted - as 
can steam plants - hut must he taXen where found, 
the general problem becomes one of relation between 
location of market for power and the source of pow- 
er generation. Ordinary commercial principles 
would usually dictate that a power development be 
carried forward only after a demand had arisen for 
power in a given locality. This is merely a crea- 
tion of supply to meet demand. There have "been, 
however, in recent water power developments - num- 
erous cases of the opposite procedure to this. In 
such projects, water powers - especially favored 
by location or proportion or both - have been de- 
veloped first and the market created afterwards, 
in range of transmission. This constitutes a for- 
cing demand in such localities - by the creation 
of an attractive supply. 



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Hydro-Electric Power Station Design 

The allowable distance between the point of 
generation of power and the point of consumption 
is therefore limited by the range of economic and 
safe transmission of the energy. As a result of 
improving methods and equipment this distance is 
gradually lengthening. Present practice does not 
much exceed one hundred miles for this as a maxi- 
mum figure. 

Outside of matters of relative location of 
market for power and the source of power supply, 
there are several important points to be consider- 
ed under the "general problem". First among these 
arises the question of the ability of the water 
supply to satisfy the market for power; that is, 
whether the maximum continuous hydraulic power of 
the source is sufficient to meet the demands of 
the market. The assumption is made that the "wa- 
ter rights" for this amount are obtainable. If 
the amount of hydraulic power thus covered is not 
sufficient , then the advisability or necessity of 



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Hydro-Electric Power Station Design 

an auxiliary steam plant must "be considered. Next 
comes a consideration of the character of the load 
That i3, the purpose for which the power is to be 
used,- -whether for lighting, for railway work, for 
miscellaneous power purposes or for a combination 
of these. If the latter, then the approximate pro 
portion of each. 

All of these points must be reviewed under a 
general survey of a water power development. 7or 
further consideration, the more detailed factors 
influencing a project must be taken up. These are 
outlined in what follows. 

The Water Supply. 

The very existence of a hydro-electric power 
generating station depends upon its water supply. 
Obviously then, the continuity and comparative uni 
formity of flow of this should be at least reason- 
ably assured. 

Power sources for such developments at pre- 
sent are chief ly confined to the fall and flow of 



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Hjrdro-Slectric Power station Design 

streams. The two main factors governing these de- 
velopments are the "head" and the volume. The 
first quantity represents the difference in eleva- 
tion between the surface of the water in the sup- 
ply reservoir and in the tailrace: that is, the 
difference in height of the water before and after 
its potential energy has been utilized. This fact- 
or is commonly given in feet. The second quantity 
is the flowtor volume of water per unit of time 
■vhich is available for use at the given head. This 
factor is usually expressed in * second- f eet "- an 
abbreviated expression for "cubic feet per second". 
The available head, for any project, is -once 
it has been decided upon - practicallj' constant. 
It may be ascertained by means of a careful topo- 
graphic survey of the stream. On the other hand, 
however, t&e second factor - namely the flow - is, 
owing to the variable quantities upon which it de- 
pends*- quite likely to be anything but constant. 

It is this factor which gives rise to most of the 
difficulties to be met in hydro-electric power sta- 



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Hydro-Electric Power Station Design 

tion work. 

A more careful investigation into the nature 
of this quantity - "flow" - will reveal the fact 
that it , liable to change from day to day, season 
to season and even from year to year. Primarily, 
it depends upon the size, contour, vegetation and 
soil of the drainage area of the stream, as well 
as upon such climatic conditions as rainfall, tem- 
perature and barometric pressure. In the calcu- 
lation of this quantity both the greatest care and 
the most conservative judgement should be used* 
Even with these detailed precautions, unusual con- 
ditions may arise at times after the project is 
completely installed,- conditions of great excess, 
or the exact opposite, in the water supply. The 
result being that a large proportion of the in- 
vestment, possibly the entire amount, will be 
rendered valuless. Such serious happenings have 
been Known to take place and nothing should be 
left undone in the way of precaution. Therefore 
all records that it is possible to obtain of the 



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Hydro-Electric Power Station Design 

flow of the stream in question should he carefully 
examined and compared, as well as careful attention 
paid to all of the factors influencing it. The ob- 
ject of such researches throughout, being to obtain 
as accurately as possible, first - the actual mini- 
mun that can be reasonably expected from the stream 
in point of constant flow, and second, the points of 
maximum discharge - together with means of conserv- 
ing the energy of such surpluses of water. 

Foremost to be considered is the drainage 
area. This should be investigated from the source 
of the stream and it 3 tributaries to its mouth. 
Area, contour, vegetation, soil and rainfall should 
be considered. Other factors the same, the larger 
the area drained, the greater the "run-off" of wa- 
ter. The contour, vegetation and soil manifestly 
influence such quantities as absorption of rain- 
fall and the evaporation of surface waters - with 
a subsequent influence exerted on the resulting 
"run-off ". The effect of rainfall on stream flow 
is positive though not absolute, as it is greatly 



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Hydro-Electric Power Station Design 

affected "by the above outlined climatic conditions. 
The dry-leather flow of a stream is not so much in- 
fluenced by the total annual rainfall as it is "by 
the distribution of such rainfall as occurs through 
out the year. In this case>as in all cases of re- 
lation of rainfall to stream flow* no absolute and 
general rule can be formulated, the problem of each 
watershed being distinctive. However there are 
some considerations common to all cases and these 
will be here briefly taken up. 

in the first place, what may be termed the 
"water year", begins approximately with the month 
of December and ends approximately with the Novem- 
ber following. This is divided into three periods: 
the first six months constituting the "storage" 
period, the next three months - the "growing" per- 
iod, and the remaining three months - the "replen- 
ishing" period. Turing the first period the winte' 
snow and the spring rains saturate the ground to a 
considerable depth, a large amount of water being 

held in storage in lakes, swamps and forests as 



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Hydro-Electric Power station Design 

well as in the soils, gravels etc. At this time 
in the year a heavy rainfall finds a quick response 
in large stream flow, for the saturated ground re- 
jects further "water, and the water runs rapidly 
from the surface. That part of the stored water oi 
this period which lies above the level of the bed 
of the stream, within the boundaries of its water- 
shed, becomes available for supplying the stream 
as well as for the purposes of surface evaporation 
and the sustaining of plant life* These waters 
will supply a certain part thereof to the stream, 
regardless of the rainfall, even maintaining a 
flow in the stream for some months without any 
rainfall. 

During the "growing" period the ground water 
furnishes practically the entire supply to the flo 
of the stream, the only additional part coming 
from an occassional rainstorm. In some cases so 
depleted does the ground water become by the end 
of August that even a very heavy rain will make no 
perceptible difference in the stream flow, the 



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ground absorbing the entire amount of the pBBcipi- 
t at ion. 

During September, October and November the 
ground begins to receive its store of water, and 
with favorable rainfalls, it becomes saturated dur- 
ing the "storage" period following. The stream 
flow is a constant drain on this supply, but in ad- 
dition to this thare is a loss of water falling on 
the watershed due first to evaporation and second ' 
that amount t ale en up by plant life. 

Having thus discussed the subject of Drainage 
Area and the influence of its various components on 
stream flow, we come to a consideration of the stre 
itself. No matter what the more or less theoreti- 
cal factors influencing the stream flow may be, we 
have finally to deal directly with the actual vol- 
ume of water flowing in the stream. To measure 
this quantity there are three general methods, any 
one of which may be used: the choice, in any case, 
depending upon local conditions, the degree of ac- 
curacy desired, the funds available, and the length 



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of time that the record is to be continued. 

The first general field method for obtaining 
the value of stream flow is by measurement of the 
slope and cross section and the use of Chezy's and 
Bitter's formulas: the second method is by means 
of a weir: and, the third by measurement of the 
velocity of the current and the area of cross sec- 
tion of the stream. Where conditions will permit, 
the second method offers the best facilities for 
determining the flow. 

The greater the period of time for which this 
data is available,- showing past performances of 
the stream under various conditions of season and 
climate- the more accurately can its future prob- 
able flow be predicted. As it is with this quanti- 
ty of "future flow" that the proposed plant will 
have to reckon, calculations for it should, if pos 
sible, be based on data for at least a number of 
consecutive years previous. 

A very convenient way of considering this is 



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Hydro-Electric Power Station Design 

to plat , ifor each year upon which data is availably 
a curve showing the relation between the tine of 
the year and the flow. The abscissae represent 
the days of the year, division points locating the 
different months, and the ordinates - the correspon 
ing flow in "second-feet*. A scale of theoretical 
hydraulic horse power may be marked off on the axis 
of (rdinates, this merely representing a constant 
times the "second- feet* of flow,- the constant de- 
pending upon the "head" and the weight of water. 
From this scale may be read direct ly the power pos- 
sibilities of the stream at any given tine. A 
straight line drawn parallel to the axis of absciss 
through the lowest point on the curve, will show 
the maximum power to be realized from the stream 
throughout the year. If the physical conditions 
of the channel and banks of the stream will permit 
of the construction of a properly proportioned dam 
together with retaining walls (if necessary), then 
the whole or at least a part of the water represent 
ed by the "peaks* on the time- flow curves may be 



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Jtydro-Electric Power Station Design 

stored up as "pondage", and drawn off at times of 
"low water", the resulting maximum constant flow 
being thus increased. The comparison of the time- 
flow curves for a number of years, on the same strea 
will show the variation to expect - at least as 
possibilities- from year to year. 

From a proper consideration ,then, of the fore 
going points - influencing the water supply of a 
hydro-electric development - nay be obtained a fair 
calculation of the power to be expected from the 
source. Prom this we are lead to a consideration 
of the exact location of the plant. 

Exact Location For Plant. 

The approximate location of a hydro-electric 
project being determined by means of the factors 
of the "general Problem", namely the market for 
sale of the energy and the source of the water pow: 
there remain but a few points which will decide 
the exact location of the plant. 

The question of "water rights" must be settle 



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Ifydro-31ectric Power station Design 

By this is meant the obtaining from the State of 
the right to use, fM> power generating purposes, a 
certain number of second- feet of water from the 
stream in question. After this, comes the matter of 
real estate on which to locate the power house and 
auxiliary water controlling works. This is, how- 
ever, usually a minor point as such property is gen 
erally some distance from centers of population, 
and hence its value is comparatively small. 

Outside of these considerations, the exact lo- 
cation of the plant should be such as to realize 
the greatest efficiency from the two controlling 
factors in any project, namely the "head" and the 
volume of water. The most available head, consider 
ing total fall and the possibilities of back-water, 
and the arrangement permitting of the most economic 
use of the volume of the water, considering the 
desireability or necessity of storage supply - are 
the two factors to be sought, with this decided wo 
pass to a discussion of the component parts of a 



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Hydro-JSlectric Power Station Design 
hydro-electric power generating project. 

Parts of the Project. 

"With the exact location of the plant settled, 
the general lay-out of the auxiliary water controll- 
ing works mast be determined upon. The devices 
best adapted to conveying the water from the source 
of supply to the wheels - form a question peculiar 
to each individual case. However, they consist - 
in general - of a reservoir, either a part of the 
stream or apart from it; a conducting pipe-line 
from this to the power house, or in the case of an 
open penstock type - a forebay, and, a tail-race, 
in this work such parts as dams, intakes, penstocks 
gates and tail-races mu3t he considered, and are 
here treated of briefly. 

Dams. 

Por water-power work. there are two kinds of 
dams most used - depending upon the material of 
their construction, the first - the earthen, and 
the second - the masonry dam. Of these two classes 



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the failures of earthen dams have been the most 
numerous, the cause being either that there was not 
the proper length of spillway, or that the outlet 
pipes were not properly laid in the dam. The re- 
quirements for stability of any dam are that it be 
strong enough to withstand the pressure of all wa- 
ter that it holds back, that it withstand leaks, and 
that it afford proper spillways and sluice-gates. 
in the construction of an earthen dam, three 
things must be considered: first, the conditions 
must be such that the maximum flood that has ever 
occurred at the site can be taken care of during 
the building of the damjsecond - the water must ne- 
ver top the embankment of the dam, - it being eithe 
led around the end of the dam or through some new 
channel; third - the proper soil should be used 
in the construction of the dam. If conditions are 
such that the flood waters likely to arise cannot 
be carried around the end of the dam during its 
construction, then the earthen dam should fcever be 



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Hydro-KLectric Power station Ttesign 

used* 

Any soil used in the construction of an earth- 
en dam should he tested for quicksand, and if any 
traces are found the soil should he discarded. 
Soils having an angle of repose of less than twenty 
degrees when placed in water should not he used. 
The "best soils for use are those containing enough 
clay to give the required water-tightness and "bind- 
ing quality,- too much of this ingredient should 
he avoided as it swells on becoming wet and shrinks 
on drying. If, during the construction the mater- 
ials are dampened, cracks and leaks are less liable 
to occur. If the material at hand is of different 
grades » the best should be placed on thsupstream 

side, gradually changing to the more porous toward 
the center of the construction. 

The profile of an earthen dam will depend upor 
the height of the dam. The slopes will depend up- 
on the angle of repose of the material used, it 
being usual to make the inner or upstream side 



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Hydro-Electric Power station Design 

flatter than the outer or downstream side, as earth 
when -jet has a flatter slope than when dry. 

Where a masonry dam is constructed more atten- 
tion must be paid to the foundation than is necess 
ary in the case of an earthen dam as any settling 
of the masonry will cause craoXs. With high mason- 
ry dams the foundations are usually made of solid 
rock. The superiority of the masonry over the eart 
en dam lies in the facts that it can he made more 
durable, can he more precisely designed, and better 
protected from flood waters^ owing to the safer 
construction it offers for the laying of the outlet 
pipes. For all dams of any height , masonry construe 
tion is to be preferred. 

The shape of a masonry dam will depend upon 
the head of water for which it is designed, for lor? 
dams the cross- sectional shape usually being trape- 
zoidal, but for high heads the sides are usually 
curved for the purpose of saving material. 

The reinforced concrete dam has some advantag 



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Ifydro-Slectric Power Station r^ign 

that the masonry dam does not possess. It can be 
made more stable than a masonry dam of the sane di- 
mensions. The materials can be distributed to -bet- 
ter advantage and therefore there will be a saving 
in cost. The interior of the dam can be inspected* 
it can be constructed more rapidly and does not re- 
quire such good foundations as do masonry dams. In 
many cases where a reinforced concrete dam is con- 
structed the power house is built into the dam, 
thus greatly reducing the cost of the project. 

One factor in the building of concrete and 
masonry dams which does not affect the earthen dam 
is the effect of ice. In countries having cold 
winters the expansion of ice is liable to be great 
enough to rupture the dam, masonry more so than 
consrete. 

"IntaKes" lead from the dam, being either sub- 
merged or at the level of the water. The flow 
through them being controlled by gates which are 
either machine or mannually operated. 



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Hydro-Electric Power Station Design 

Penstocks. 

The cheapest form of penstock is the circular 
wooden stave penstock. The staves should be as fre 
from knots as possible and should be smoothed on 
the inside in order to reduce friction and get the 
maximum efficiency. 1 Vhere the stave penstock is 
installed it is common to have all bends and curves 
in the line of steel pipe, unless the curve be of 
large radius. Iron hoops or bands are used to hold 
the staves in place, their spacing depending upon 
the initial tension, the water pressure, and the 
swelling of the wood. 

Steel penstocks are especially adapted to long 
pipe lines, as oft en, in such lines, abnormal press- 
ures are developed due to the sudden shutting-off 
of the water from the turbines. In order to regu- 
late this pressure, a small reservoir is construct e 
at the outlet of the penstock, the size of this 
reservoir depending upon the time it takes to close 
the turbine gates. In place of the reservoir 



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a steel standpipe is sometimes used, the water run- 
ning over the top of the standpipe if the gates he 
closed too suddenly. If the fall of the pipeline 
he too great for standpipes, safety valves are plac 
©d along the line of the penstock. The life of a 
steel penstock is sometimes vary short due to the 
rusting of the steel, though this action may be 
greatly reduced by treating the penstock with hot 
asphaltum. At the entrance to penstocks, racks 
should be so placed as to collect all floating ob- 
jects and not allow them to pass into the pipe. 
In cases of ice formation these racks may become 
clogged if the ice is not removed on forming. A 
large, deep forebay will remedy this troublB, as the 
water,being quiet here, will freeze over at the be- 
ginning of cold weather. Then such anchor ice, as 
may come into the forebay, will rise to this layer 
of ice, while the warmer water will circulate belo- 
If the intake to the penstocks be so located as to 
receive this water, there will be little trouble 
from i~e a ^ the racks. 



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Tail-race. 

This should be deep as it is necessary to have 
dead water in the race before the wheels are start- 
ed. As soon as water is discharged from the wheels 
this will tafce the place of dead water and thus 
there will he no resulting loss of head. It is us- 
ually necessary to place the wheels at some height 
above the tail-race, the water after leaving the 
wheel passing through a draft tube. This draft 
tube should be air tight and submerged - at its low 
er end - in the water of the tail-race to prevent 
any loss in head. 

Power House Equipment. 

Water v/heels. 

These may at once be divided into two classes - 
impulse wheels and turbines. The former is typi- 
fied by the Pelton Company's wheel, in which the 
velocity of a Jet of water impinging tangent ially 
upon a disc, carrying buckets around its periphery, 
transmits to the buckets a part of its velocity. 



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It can be shown that the efficiency of the trans- 
formation is a maximum when the velocity of the mov 
ins buckets is one half that of the jet, so that if 
H is the effective head of the source, for maximum 
efficiency, the peripheral velocity of the wheel is 
related to the head by the expression: 

▼ « r= .5 /glT 

and the head being assumed invariable, it is seen 
that for a certain definite speed (imposed by the 
frequency of the generator), the only variable is 
the diameter of the wheel and this may be adjusted 
within cdrtain limits, to conform to the relation 
above. Thus direct connection of the generator 
to the source of power is possible, which eliminate 
the losses in transmission through gearing and the 
noise incident to its use. 

These -"Theels require that there be sufficient 
distance between the wheel and the highest point of 
backwater, to allow for the discharge of the spent 
water from the buckets of the apparatus, and for 



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Hydro-Electric Power Station Design 

a variable height of hack water at different sea- 
sons of the year, this involves a serious loss of 
head. Also, since the action of the machine depend 
upon the velocity of the Jet, which in turn depends 
on the square root of the head, the Pelton wheel 
is only available with any great efficiency when 
the head is great, i.e. above three hundred feet. 
In general, then, its use should not be considered 
with heads less than this. 

Water turbines are available for the lower 
heads, since they do not depend entirely upon the 
velocity for the necessary Kinetic energy - the 
large mass of water obtained may reduce the necess 
ary velocity. These machines are typified by the 
products of the James Leffel Co. , the S.Morgan Smi 
Co. and many others. Under favorable conditions 
they give an efficiency of from eighty to eighty- 
two percent , and may be obtained in the horizontal 
or vertiole form. The verticle type, on account 
of the reduced friction losses caused by the lesse 
ed friction in the bearings, gives an efficiency 



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Hydro-Electric Power station Design 

about three per cent higher than the horizontal 
type, exclusive of gearing, hut due to the fact 
that gearing is necessary to change the direction 
of motion, involving a loss of about ten percent, 
the actual net efficiency is reduced approximately 
seven percent unless the generators are of the ver- 
tical type also. Horizontal wheels are favored 
because they permit the use of several units on one 
shaft, and if this number is even, the unbalance 
of pressure caused by one unit i3 taken up by the 
next so that the friction loss is diminished. In 
order that vertical units may actuate one shaft, 
this shaft must be horizontal to conform to prac- 
tical conditions and the use of vertical generators 
as was noted above, is precluded, and there is also 
introduced the loss due to the gearing which must 
be installed* 

In choice of prime movers it is therefore 
necessary to consider:— 

1. The available head, which will determine 
practically the availability of Pelton or tufcbine 



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Hydro-Electric Power station Design 

wheels by the condition that for heads above three 
hundred feet the Pelt on wXeel is to be preferred, 
for heads less than ^wo hundred feet, the turbine, 
and for intermediate heads, either one indifferently. 

2. The type and speed of the units and their 

capacity, since for generators of large size it may 

be necessary to install several units on one shaft, 

which involves the difficulty mentioned above, and 

1 
the restrctions that limit the generators of the 

horizontal type. 

3. In addition to these conditions, which 
must hold generally, others are imposed when the 
head is not constant, that is, when the backwater 

is variable. In this case the velocity of the wheels 

will not be constant, and since the generators are 

practically constructed to operate at a constant 

frequency, this variation could not be allowed, even 

if the field rheostat of the machine were capable 

a 
of taxing up the increase or decrese of pressure 

at the terminals. Also, since a decrease in speed 

will decrease the output, it would be necessary, 



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Itydro-Electric Power station Design 

even in the above case, to install a gseater cap- 
acity than would be required at the normal full- 
load speed and tche disadvantages noted would still 
be present, 

in this case it is necessary to install another 
wheel is geared with a higher ratio to the line 
shafting so that when the head is decreased this 
wheel may be thrown in with the other one, their 
speed then being a mean between the two and the 
decrease in output of the first being supplied by 
the second. If the variations in head are very 
wide, it may be necessary to install several of 
these additional wheels and allow them to run idle 
during the normal operation of the plant. This 
extra installation of course involves a higher first 
cost and is to be avoided if possible. 

In the choice of the number of units there 
should be considered the over load capacity of the 
units so that when one is disabled or shut down 
the remainder of the plant may carry the load with- 
out exceeding the allowable overload rating of each 



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Hydro-Blectric Power Station Design 
unit, it is common practice to decide on this rat- 
in* as 33$, and it then follows that four units 
are necessary since on may then be cut out and the 
re- 6 can carry 33$ overload and maintain the nor- 
mal ouput of the plant. 

Generators! — The first classification of gen- 
erators is into the direct and alternating current 
machines, and the choice is determined "by the char- 
acter of the load and the transmission distance. 
Ws assume that this distance is not short enough 
to warrant the use of direct current, and proceed 
to consider the features which determine the choice 
of alternators. The problem for di»ect current 
transmission is much simpler, and nay be solved 
by neglecting the factor of frequency. 

The conditions determining the frequency are 
the character of the load and the transmission; 
for example if the power is to be supplied to 
svnehronous converters the frequency should not 
exceed forty cycles, and to conform to the apparatus 
already in stocR in the manufacturing concerns, 
this figure should probably be chosen at twenty- 
five* Page 

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Itydro-Electric Power Station Design 
This is also suitable for transmission and power 
service, but has the disadvantage that incandescent 
lamps do not operate well at this frequency so that 
if the lighting load 4s not concentrated in cities 
where it may be supplied by synchronous converters 
it may be Aecessary to install frequency changers. 
At sixty cycles' this difficulty would be avoided, 
hut converters do not operate at this frequency 
with any great stability, and the conditions of 
constancy of service demand that the substation 
operation be as nearly perfect as possible. 

If it is found desirable to use this higher 
frequency, induction motor-driven generators may 
be installed for the conversion to direct current, 
but this eliminates the possibility of compensation 
for lagging current in the line, and this difficulty 
may be of considerable magnitude if the line is 
to supply power to induction motors along the right 
of way. 

A careful consideration of the load to be sup- 
plied will therefore be necessary in order to deter- 
mine the frequency at which the current is to be 

supplied. Page 

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Hydro-Electric Power Station Design 

The voltage to be generated by the machines 

is of little importance if it is to stepped up 

e 
for transmission, so that this fact must "be dter- 

mined. The highest voltage at which it is practic- 
able to generate is about 11,000. in deciding upon 
the transmission voltage it is common practise to 
figure roughly upon a thousand volts per mile 
within the limits of safety, which is set at 80,000 
volts in this country* we therefore decide that 
if the distance to which power is to be transmitted 
exceeds ten or fifteen miles it will desirable to 
stop up the pressure and generate at such a potential 
that the insulation of the machines will not be 
in danger nor will the armature be forced to carry 
excessive current. 

It having been decided in the preliminary in- 
vestigation what will be the capacity of the plant, 
the next step is the division of units. The same 
conditions which govern the nia&nber of prime movers 
apply here and we may state that there should b« 
at lea»» four units, a greater inumber being of course 
necessary when the output of the plant is so great 

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Hydro-Slcctric Power Station Design 

that four units of the largest commercial size 7d.ll 

not carry the load. 

We now have the frequency and capacity of the 

generators and desire to Know the speed at which 

they will operate. This speed is limited to certain 

definite values by the limitation to constant frequency 

so that the r.p.m. must satisfy the relation: 

60 f / p a n 

where p is the number of pairs of poles and f the 

frequency. From this relation the following table 

may be made showing the number of poles for each 

speed to give the desired frequency and the catalogs 

of the manufacturers may then be consulted to d.b- 

termine the machine to use. Before settling upon 

a unit the peripheral velocity of the rotating parts 

should be calculated in order to ascertain if this 

value is too high for the safie operation of the 

machine* if this is the case it will be necessary 

to choose a machine with a greater number of poles 

and a slower speed. 

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Hydro-Electric Power Station Design. 

The generators should if possible be direct- 
connected to the prime movers to eliminate any fric- 
tion losses in the transmission and this fact neces- 
sitates a consideration of the speed of the wheels* 
Thi3 speed is determined by the effective head, and 
in t r he case of the Pelt on wheel it was shown that 
the diameter of the wheel could be varied withinn 
certain limits to compenstae for any disagreement 
between these twp speeds. In the case of the tur- 
bine, however, this compensation is not always pos- 
sible, although the manufacturers have in stock a 
great variety of wheels which will generally give 
the desired relation. If this cannot be obtained 
it will be necessary to gear the wheels and the 
generator can then be made to run at any speed, 
the desired frequency being obtained, by the ratio 
of the gears- 
Exciters:— From two to three percent of the 
output of the plant is required for the excitation 
of the units, so that this much mist be added for 

Pag© 
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HSrdro-Electrio Power Station Design- 

the gross output of the plant if the initial cal- 
culations are sufficiently close to warrant con- 
sideration of Quantities of this magnitude. The 
exciter plant is the weaX linh in the system and 
great care must "be exercised in the installation 
of the units. Several facts may be noted In this 
connection, 

lm There should he two independent sources of 
excitation which may be readily interchanged so 
that in the event of one "becoming disabled the 
operation of the system may not be suspended for 
anyconsiderable period. 

2. Tfte prime movers or other apparatus driv- 
ing the exciters should al#> he independent and 
capable of operating in parallel so that in the 
event of the failure of one system the other may 
be automatically thrown into service without the 
delay incident to the manial operation of the 
necessary switches* By this is meant that the 
exciters should be provided with reverse current 

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Urdro-Eldctrlc Power station Design 

relays so that in case one of the prime movers 
fails and the generator thereby becomes motorized 
the other may pick up the load while the first is 
automatically cut off from the exciter bus. His 
means that each system must be capable of carrying 
all the excitation necessary for the plant at any 
time, and since the breakdown of apparatus usually 
•ccurs at times of heaviest load, this consideration 
is of fundamental importance. In water-power sta- 
tions the sources of power may be water— driven 
wheels for the operation of one system and motors 
for the other. In this case the motor-driven ap- 
paratus must be kept constantly in operation, since 
if this were not the case the failure of the water- 
driven exciters wo't^d disable the plant. At times 
of light load, however, it will be safe to operate 
the plant with but one set of exciters, since the 
possibility of the break-down of apparatus is slight 
and more is to be feared from the mistakes of the 

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Hydro-Electric Power Station Design 

operators than from faults of the machines. 

Transformers: — it having been decided that 
there -grill be a definite number of phases — usually 
three— arid the transmission voltage baling known, 
the transformer problem becomes simply a phoice 
between the adoption of three single-phase trans- 
formers connected up to give the desired relation 
of e.m.f's or one three-phase transformer for 
each unit. The conditions influencing the choice 
are as follows: 

1* The distance from the nearest shipping 
point to the power station — this enters in because 
of the fact that large transformers are more dif- 
fi cult to handle than small ones, and if, as is 
usually the case, the power house is located in a 
mountainous country, the smaller units would pro- 
bably be chosen, since the cost of transportation 
will overbalance any saving in first cost. 

2. The facilities for the handling of the 
apparatus at the "newer station, such as cranes, 
labor, etc. The use of the larger units of cduree 

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Itydro-siectric Power station Design 

makes necessary a larger crane. 

3. The necessity for a spare unit. In the 
case of three single phase unit 3 the connection 
may be so made that any one of the transformers in 
the station may be disconnected if injured and the 
spare put in it 3 place by means of air-break dis- 
connecting switches. If three units are employed 
a three phase unit may be usdd as a spare and the 
increased cost would make an installation of the 
single phase units desirable. TSiis consideration 
vanishes when the size of the station is great or 
the units numerous, since the additional compli- 
cation of circuits due to the installation of 
disconnecting switches more than balances the extra 
cost of the three phase unit. 

4. If one of the single phase units becomes 

burned out it may be removed, but in the other 

case the whole transformer will need to be removed 

unless it is connected delta and allowed to operate 

with a v-connection at 58$ of its firmer output. 

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Hydro-Electric Power station Design 
The large units are in general desirable if 
the objections mentioned above do not operate, 
for they are more compact , all the coils in one 
case and the installation is less complicated, also 
the first cost is less. A disadvantage is,, that 
since the surface of a tr nsformer and its output 
do not vary uniformly, but the surface less rapidly, 
the cooling of the larger sizes will be a more sftr— 
ious problem. This however may be accomplished 
quite readily by the use of fans for circulating 
the air through the coils» 

Instruments and "firing: — These switchboards 
may be separated into two parts, the exciter board 
and the mainboard, and these may be concentrated 
in one position or separated, according to the size 
of the station. When the size is sufficient to 
warrant the constant attention of two operators, 
the exciter board may be isolated and loeated near 
the exciter units, the other being placed in a 
gallery, fhen this arrangement is adopted one op- 
erator may take charge of the exciter board and 
look after the units on the main floor while the 



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J$rdro-Slectric Power Station "Design 
other confines his attention entirely to + 'ie opera- 
tion of the lines and units, where theplsat is 
used to supply a large number of lines it is pre- 
ferable to have the oil switches located in a room 
by themselves with an attendant there to unlock 
them, preparatory to their closing, at a signal 
from the operator in the gallery. This eliminates 
the danger of closing a dead machine on the line 
or other machine by mistake. 

This segregating of switchbords and swithhes 
makes a more expensive construction and where the 
first cost is anitem, or where the plant is small, 
the switchbords should be concentrated. In hydro- 
electric plants, where the lines ire in general 
long ones, and this fact precludes the possibility 
of a large number of them, the operation of the 
lines will not be necessary more than perhaps once 
a day, so that the above mentioned precautions need 
not be taken in their operation. 

The following instruments should be located 
on the main switchboard* For each generator panel, 



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Hydro-Slectric Power Station Design 
three ammeters, three indicating wattmeters, ene 
voltmeter with selector switch for each phase, one 
integrating wattmeter, and one field ammeter. 

The switches and auxiliary apparatus shoild 
comprise: An oil switch control for thrwing the 
machine to H.T. "bus, generator field switches, 
and a field rheostat control. The field switches 
should he equipped with a clip for short-circuiting 
the generator fields through a resistance when the 
switch is opened, thus avoiding the introduction 
of stresses into the windings by the induction of 
a high potential at that time. 

The exciter equipment should consist of an 
ammeter and voljrmeter for each unit, swithes for 
throwing the exciter to the exciter bus, field 
rheostats for the voltgge regulation, and the 
necessary equipment for the operation of the prime 
mover* If this is a motor there should he an in- 
tegrating wattmeter to register the power consumed 
in excitation. Equalizers should also be installed 
if the exciters are compound wound and designed to 
operate in parallel. 

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Itydro-Electric Power Station Design 

On the high tension side there should he over- 
load relays on each phase* actuated from series 
transformers and esigned to open the generator switch 

at any desired overload and after any desired in- 
terval. These should he of the bellows type* 

In the station some kind of frequency limiting 
device is necessary to trip out the machines should 
they have a tendency to race beyond control. This 
may be of the inductive balance type or purely me- 
chanical, and a common practice is to design the 
instrument so that it will operate at a frequency 
ten percent above normal. This values seems somewhat 
low for isolated plants, and fifteen percent would 
appear to be better. 

Governors actuated ey an electrical connection 

with the load ammeters have been suggested in order 

to eliminate the time necessary for the system to 

change in speed, but the idea has not as yet been 

tried, and seems not to find favor with the designers 

of these plants. 

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AHMOTTR 

INSTITUTE OF TECHNOLOGY 

LIBRAKY 



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Part II. 



Design for Proposed Hydro- 
Electric Power Generating station, 
Malad River, Idaho. 



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Kydro-Electric Plant,- Malad River, Idaho 

Introduction. 
In undertaking the actual design of a hydro- 
electric power plant, it was desired to have as 
near worXing conditions as possible- The selec- 
tion of the location on the Malad River, Idaho was 
made after data had been secured which gave the 
exact conditions that existed at this point. 

The General Problem. 

The source of the power for the proposed plant 
is from the Malad River - a tributary of the snaXe 
River: the two meeting in the western part of Liiv- 
coln county, which is located in the south- central 
part of the state of Idaho. 

The present marXet for power from this source 
is that offered by the city of Boi3e - for light 
and power- a hundred miles distant: the town of 
Glenns Perry - principally for light - thirty miles 
distant: and locally, within a radius of from five 
to ten miles - for irrigation pumping purposes. 
A possible future marXet consists in certain rail- 



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Hydro-Slectric Plant,- Malad River, Idaho 

road electrifications that have been proposed in 
the vicinity. 

No continuous record is available on the flow 
of the Malad River* but from such readings as have 
been taken of this quantity, it 13 evident that 
there is a uniform volume of water in the stream 
highly sufficient to carry a plant of 4800 kw. - 
ouch as is here proposed. This allows for the di- 
version of small quantities of water for irrigation 
purposes, these being protected by existing water 
right s. 

The ^ater Supply. 
The Malad River is supposed to be the outlet 
for both the Big ^ood and the Little ^ood Rivers. 
These latter rise on the southern slopes of the Tetan 
Mountains which form a water shed extending along 
the northern boundary of Blaine county, Idaho. Prom 
here the rivers flow southward, fed by numerous 
smaller streams,- a distance of some hundred and 
fifty miles. At this point they join, disappearing 



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Hydro-Blectric Plant,- Malad River, Idaho 

from the surface of the earth. Ten miles farther 
on the Malad RLver rises - being the accumulated 
waters of thousands of springs. The theory being 
that the Wo rivers - the Big Wood and the Little 
Wood - after leaving the surface, traverse a sub- 
terranean passage which terminates under the springs 
which form the nucleus of the Malad River. The 
water of the Malad is a constant in temperature 
almost throughout the entire year, this being at 
about 60 Ph. The course of the stream, from the 
springs that form its source, lies through a box 
canyon about three miles in length - to the south 
west, where the Malad empties it3 waters into the 
SnaXe River. 

The drainage area of the Big Wood and Little 
Wood Rivers constitutes what is Known as the "Big 
Camas Prairie", which lies chiefly in Blaine and 
Lincoln counties. The rainfall over this area is 
fairly uniform in its distribution. The walls of 
the box canyon through which the Malad flows are 
composed of lava and basalt rock. For a short dis- 



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Hydro-Electric Plant,- Malad River, Idaho 

tance its banks arecovered with volcanic dust over 
which there is a sparse growth of sage brush. 

The General Lay-out, 
A reference to the "Map of Project *, shown in 
the second illustration, will give an idea of the 
general lay-out as designed. At a point,* mile 
and a quarter from its Junction with the snake 
Hirer, a dam is to be constructed across the Malad. 
An intake located here leads into an open channel 
through which the water is conveyed to a reservoir, 
from which it falls to the power house through a 
circular steel penstock. 4 spillway is located 
at the reservoir - for discharge into the Snake 
River direct. A controlling gate is located at 
the head of the penstock. 

Power House. 
The power house is to be located on the bank 
of the snake River. In construction it is to be 
two stories in height, of concrete throughout. The 
foundations consist of layers of concrete resting 



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Ifydro-Electric Plant,- Malad Hiver, Idaho 

on bed rook. 

Equipment • 

Water-wheels, unlike electrical apparatus, 
are not rated to carry ally overload, ao that any 
that is necessary to allow the shutting down of 
one of the units must he provided by installing 
wheels of the maximum capacity to be obtained at 
any time. The capacity of the station being 4300 
kw. , the installation will therefore be of four 
2000 H.P. wheels, thus allowing an overload capa- 
city of the desired amount. After considering the 
various types of wheels it was decided to adopt 
the type manufactured by the James Leffel company. 
These aroof the horizontal type, direct-connected, 
and are especially designed for the head considered- 
185 feet. The efficiency at full load is found 
to be 89$, at three-fourths load 83$, and at half 
load 75$. The maximum efficiency is therefore ob- 
tained at the output of the apparatus which corres- 
ponds to full load on the generators, and any over 
load will somewhat lower the efficiency. 

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Itydro-Electric pi an t,- Malad River, Idaho 

The diraemsions over all are eighteen feet by 
seven feet, eight inches, the diameter of the in- 
take sixty inches, and of each of the tw draft 
tubes - at the lover end - forty-eight inches, and 
at the outlet - thirty-t?ro inches. Details of these 
wheels are shown on Drawing No. Till. 

Due to the peculiar advantages of the ground 
lay-out it is decided to bring the water into the 
power house overhead, by means of the large pipes 
shown in the drawings. These derive their power 
from the main penstocks, which is eleven feet in 
diameter at the outer end and narrows down to five 
feet for the last unit. 

The governors used are of the standard type B - 
Lombard, and are purchased with the turbines. These 
operate by means of a mechanical connect ion with 
the units instead of by means of an electrical con- 
nection wi th the ammeters, as has been suggested in the 
first part of this paper. The estimated loss of 
time in their operation is approximately one second 
and is due to the large amount of inertia of the 
rotating parts, further loss of time is eliminated 

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Hydro-Electric Plant,- Malad River, Idaho 

by the installation of a reservoir near the station 
of sufficient capacity that the water level will 
never fall appreciably when a sudden demand is made 
for power. The time taken for the pulse to reach 
the station from the d*m will he the distance divided 
"by the velocity of sound in water. 

Choice of generators is largely a natter of 
persons opinion, since the output of the large 
manufacturing companies is of a high degree of ex- 
cellence. Due to the restrictions on the frequency 
noted above, this figure waa taken at twenty-five 
cycles. The speed is therefore limited to the values 
given in the first part of this treatment under 
the head of Electrical Units. The values are, 300, 
375, 750, etc. Since direct-connection with the 
water wheels is desired » the speed which was decided 
upon was 375 r.p.m. in order to conform in speed 
with the water wheels selected. This is a standard 
machine fori the capacity wanted - 1200 Xw. - 
so that no trouble was experienced due to too high 



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Hydro-Electric Plant,- Malad River, Idaho 

a peripheral speed. 

The transmission distance ( maximum) is one 
hundred miles, so that there will be the necessity 
of stepping up the voltage for transmission, and 
the pressure of the machine is immaterial within 
wide limits. This figure was taJcen ai> 11,000 volts 
for the following reasons: Part of the power is 
to be transmitted a distance of thirty miles and 
it is desireable not to retransform this power from 
the extremely high voltage for the longer transmis- 
sion. The machines are therefore connedted direct- 
ly to a "low tension* bus, at a pressure of 11,000 
volts and the power for the shorter transmission 
istaken from this bus» while the transformers are 
fed from the 11,000 volt bus and transform the 
pressure from that to the value required for the 
longer distance. 

Since the rough approximation for the trans- 
mission voltage demands a pressure of 100,000 volts, 



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Hpdro-giectric Plant,- Malad River, Idaho 

and this is at present beyond the capacity of the 
insfclators available, the voltage decided upon was 
66,000, giving a value of volts per mile as 660, 
which is in accord with modern practice. 

As was noted above, it is necessary to have 
two independent sources of excitation, and this is 
accomplished by means of the motor-and water-wheel 
driven units shown in the drawings* Greater 
dependence will be placed on the water-wheel-driven 
apparatus, so that two of them are installed and 
the motor—driven unit is to "be used in emergencies, 
and to run in parallel with the others during the 
peak load or at times when a shut down would be 
most disastrous. 3ach of the exciter units are of 
75 kw. capacity and the motors and ^ater-wheels 
of 100 HP each. The power for the motor-driven 
exciter will be derived from a transformer fed 
from the "low tension" bus, the e.m.f. oeing step- 
ped down from 11000 to 22o volts. "Die motor is 
of the induction type and is started by means of 

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Ifydro-Electric Plant, — Malad River, Idaho 

the special starting taps shown diagramraatically 
in the wiring diagram. This dispenses with the 
necessity for auto-transformers* and the more 
expensive construction entailed. It will he ne- 
cessary only to bring out two additional leads 
from the secondary of the transformer, and since 
this may he located at no great distance from the 
exciter, the expense will he small compared with 
that incident to the use of an auto-transformer. 

By thus dividing the units there is no danger 
that the excitation of the fields will be lost at 
any time except under the most extraordinary con- 
ditions. These precautions are necessary due to 
the fact that the exsiter system io the weaXest 
part of the plant and the greatest care must be 
taken in its design if continuity of operation 
is expected. 

The conditions influencing the use of singlf 
or three phase transformers were noted above. In 
this case it was decided to. install single phase 



units due to the fact that the country is rough 



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Hydro-Electric Plant, — Malad River, Idaho 

and the distance to -which they must be transported 
is rather large. It aloo makes necessary the in- 
stallation of a comparatively cheap unit only, this 
being placed somewhere on the floor of the trans- 
former room and connected in as desired by means 
of flexible leads. 

The capacity of the transformers will be ten 
percent greater than that of the generators to con- 
form with common practice, 30 that each unit must 
be rated at 440 lew. These are to be connected up 
delta on both sides. This is also an additional 
safeguard, since in this case if one of them becomes 
burned out , the other set can then caryy 58$ of 
the load with the same heating by operating on a 
V-connection, and, the continuity of the service 
need not be interrupted during the time necessary 
for the installation of the spare unit. 

On account of the character of the load the 
operation of the lines Trill not be necessary more 
than once or twice a day and therefore attendance 

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Hydro-Electric Plant , — Malad River , Idaho 

of an operator on the switches will not be neces- 
sary. These switches should be located , however, 
in another room to protect them ffom the dampness, 
and to insure their proximity to the high tension 
buses. For this reason they are to be located up* 
stairs where they can be readil3 r reached from 
the lower floor by the two stairways. The high 
tension buses are also located fcere so thata 
minimum amount of copper is required. The two buses 
run parallel throughout their length, asshown, and 
this makes it possible to extend the plant at any 
time by merely tearing out the end -alls and instal- 
ling a new unit. The buses can then be extended 
also and the station will then be symmetrical as 
before. 

The drawings showing the arrangement of the 
above specified apparatus and machinery are repro- 
duced in the following pages. 



Page 
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ARMOUR 

INSTITUTE OF TECHNOLOGY 

LIBRAS? 



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DRAWINGS 
for proposed 
HYDRO-^SOTKEC VO^im PLANT 
Malad River, 
Idaho. 



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Itylro-Electric Plant — Malad River, Idaho. 



Transmission of Power: — There are to be two 
36000 volt three phase, twenty- five cycle transmis- 
sion lines from the plant to Boise City and to 
Glenn's Perry, Idaho. In addition there are two 
11000 volt lines to supply po"-er for public pur- 
poses in the vicinity of the plant. The calcul- 
ations for the 66000 volt lines follow: 

Boise City line, 100 miles long, 3200 kw. 
to be transmitted, transmission voltage, 66000 



Line loss 
Res. per wire 
Sixe of wire 
Distance between wires 
induct anoo per wire 
Capacity to neutral 
Natural frequency 
Charging current 
Ind. reactance 
Cond. reactance 
Reg. no load 



256 kw. 
109 ohms, 

• 3 Band S. 
6 1 — 6" 

• 21 henry s 
1. 36 x 10" 
470 cycles 
8.2 amp. 

33 ohms 
4670 • 

• 374fj 



3 



f/mile 



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Hydro-Electric Plant,- Malad River, Idaho 



Reg. full load 


8.1 $ 




Reg. 85$ power facto? 


4.3 # 




Wt. copper 


252,642 # 




Spacing of poles 


45/mile 




Number of poles 


4,500 




Glenn's Perry 


Line. 




30 miles long, 800Kw. 






Transmission voltage 


68,000 




Line loss 


1.8 $ 




Resistance per wire 


97.5 ohms 




Sise of wire 


#8 




m stance between -wires 


6' - 8" 




Inductance per wire 


.068 henrys 




Capacity to neutral 


-8 
.375 x 10 


fAii: 


Natural frequency 


1,570 




Charging current 


2.25 amperes 




Ind. reactance 


10. 6 ohms 




Cond. reactance 


17,000 ohms 




Reg. full load 


♦ 05 c p 




Reg. 35$ power factor 


.08 <jo 




Number of poles 


1,350 


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APPODIX 



Hydro-Electric Power Station Design. 
BIBLIOGRAPHY. 

Hydro-Electric Power Plants; Beardsley. 
Transmission or Water Power; Adams* 
Standard Handbook for Electrical Engineers; MeGraw 
Water Supply Papers; U. s. Geological Survey. 
*Totes and Designs on Hydro-Electric Power Stations, 

American Institute E. E. , 25:163, Apr.06 
Location of Electric water Power Stations, 

Gassier 3, 25: 498. 
Electricity from Water Power, 

Elec. Eng. , 34: 294 
Modern Power Plant Design and Economics, 

Eng. Mag., 88: 689, 812. 
■ ■ 30: 71, 182. 

Use of Pacific Coast Water Powers in Electric Op- 
eration of Railroads, 

Jour. Elec. , 15: 115. 
Sixth Biennial Report , 1905 — 8 

State Eng. Idaho. 
Water Power" of the Rock River: Mead. 



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J^rdro-^ectric Power Station Design 



PRICES and COST ITEMS. 
(Malad River Project) 

Hydraulic Turbine Units- 
Including draft-tubes and type "3" 
Lombard Governor. Gross weight about 
75,00 pounds. P. 0,3. cars at factory, 
each - 

$ 7,800.00 

Steel Penstock - 

Circular in form: of riveted steel 
plates, with necessary saddles and 
stiffeners. Per lineal foot (about ) - 

6 46.00 

Wooden stave pipe at about half 
this figure. 

Nearest railroad connection - at 31iss, Idaho (three 
and one-half miles) : Oregon Short Line. 

Freight rate to this point, from Chicago, 
on eledtrical machinery about 1 1/2 cents 
per pound. The rate on structural steel 
from Pueblo to Bliss,- about 75 cents a 
hundred. 

Cement : about $3.35 a bbl. , f.o.b. Bliss. 

Sand, rock and gravel to be had on the work. 

Suitable poles for the transmission ( thirty- 
five to forty feet long) can be had on the 
work for about $5.00 per pole. 



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Hydro-Electric Pcver Station Design 



Market for poirer - 

Transmitted and districted to 
Boise - 100 miles,- 2-1/2 cents 
a lew. hour. 

To Glenns Perry - 30 miles, - 
5 cents a kw. hour. 

For pumping purposes in vicinity 
of plant,- 1-1 /s cents a tar. hour. 



Transmission Lines. 

To Boise (100 miles) - 

Cost of copper $ 37,296.00 

• ■ poles 18,900.00 

cross arms 3,150.00 

insulators 23,625.00 

—^ rr onri r\r\ 



pins 

Total 



7,200.00 
$ 90,171.00 



To Glenns Perry (30 miles) - 



Oost of copper I 3,566.00 

* ■ poles 5,670.00 

" " cross arms 945. 00 

n " insulators 7,088.00 

■ * pins 2,160.00 

Total I 19,429.00 



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